Thanks a lot for your review! I'm not an experienced model kit builder at all but I really have had my fingers on the Buy Now for this bridge. It looks really nice in layouts and I'm in a need for a large bridge like this one but after reading your review I think it's a on a level, or two, above my experience level.

Very cool build, and from the complexities you describe, that Faller kit is unsuited for the longer bridge I'd need to build (close to 198cm total length), as I suspect there are no middle extensions (since the support must be an arch), and the whole assembly seems very prone to breakage on its own. I take it the track spacing turns out not to be an issue? On the photos it looks like there is plenty of space.

Very cool build, and from the complexities you describe, that Faller kit is unsuited for the longer bridge I'd need to build (close to 198cm total length), as I suspect there are no middle extensions (since the support must be an arch), and the whole assembly seems very prone to breakage on its own. I take it the track spacing turns out not to be an issue? On the photos it looks like there is plenty of space.

If you could use two of them, the concrete pillar in the centre could be common to both bridges, then the rail bed between the two would be shortened. That would bring them back to very close to the length you want.

Very cool build, and from the complexities you describe, that Faller kit is unsuited for the longer bridge I'd need to build (close to 198cm total length), as I suspect there are no middle extensions (since the support must be an arch), and the whole assembly seems very prone to breakage on its own. I take it the track spacing turns out not to be an issue? On the photos it looks like there is plenty of space.

Thanks.

I don't think two bridges connected together would look right, as they are clearly designed to be supported by valley sides.

The track spacing issue was solved by the creation of a new top deck that is also 115mm wide. With that modification I think it looks fine even without side railings. The original top deck was also 115mm wide but 15mm was taken up on both sides by a walkway. If I had not added the new deck, tracks would be about 1.5mm lower along the middle axis of the bridge becasue the stupid walkways are 1.5mm higher. If they had not made the walkways higher, the flexibility of the model would have been greatly improved.

Very nice. Love the way this is turning out. I went checking (as I was thinking about my upcoming layout and would I need to integrate K-track for at least the bridges, which I may do anyway for 'flextrack' reasons) and found that C-track would also be fine if I bring the ballast between/along tracks up to the top level (fill with foam and top coat with a matching ballast) .. so for me its good to know either C or K track are fine on a bridge.

Just a side not to your blogspot and this is more an indication of filtering, some corporate proxies have issues with some of the images (could be they are filtering on some specific server names due to past incidents). But some images dont' show up for me (behind a corp firewall/proxy) while others due. This isn't an issue for home users that dont use highly manged web proxies.

I assume its in the server name or ip address as they come from different machines.The message I see when I view the image file itself is "The proxy server is refusing connections". The result when viewing the whole webpage is that some images appear non-existent.

thanks for the heads up about some proxies not allowing some images through... I suspect some other blog (or image) was blacklisted using the 2.bp.blogspot server and so nothing from that server will be let through. These are all Google hosted servers, I don't think I can do anything about it.

Note that the Bietschtalbrücke is not really made wide enough for two tracks with 64mm spacing, so I had to manufacture a new 'top layer' to handle my mainline standard track spacing.

I saw on Youtube a curved Bietschtal bridge in some layouts, likely based on the Faller kit.I wonder how they did it. Inserting some spacers in the rear side ?

singe track or dual tracks? A single track can easily be curved on the bridge but the space allocated for tracks on the bridge is not properly wide enough for 64mm track spacing double tracks even when straight!

having two together certainly is impressive, but splitting a mainline double track to 4 tracks just to go over a bridge makes no sense to me at all.

It not like one can run 4 trains over there at the same time either. The 3rd and 4th ones will have to stop on the bridge!

Expensive bridges usually would constrict a double track to a single to avoid the expense of additional bridgework, not the other way around. In fact, the prototype for this bridge initially carried a single track for many decades and then a second track was added later.

Yeah, from an economics point of view thats a dodo bird... as the 4 lines all merge down to 2 on the far side (in them image) the same merging down to 2 would happen before the bridge , and then build a much less expensive bridge. But when has economics ever played a role in model railroad hobbying. (yes thats a word now)

If, the owner of the layouta did not go to the normal school playing small rail from the starting circuits to stacking somethingcloser to real life. This is his first layout (which I called impressively) and is not burdened by the need for a realistic look.

I saw on Youtube a curved Bietschtal bridge in some layouts, likely based on the Faller kit.I wonder how they did it. Inserting some spacers in the rear side ?

singe track or dual tracks? A single track can easily be curved on the bridge but the space allocated for tracks on the bridge is not properly wide enough for 64mm track spacing double tracks even when straight!

Interesting. I wonder if the bridge support structure is always straight, and the deck part is curved to sit on top of the structure.From an engineering standpoint, and the way the forces work on the supports, I would think a curved (sideways) support structure would be a problem because the forces don't push into the mountainsides and along the length the way the arches and triangles can absorb them - those lateral forces that would result from a curved bridge would require much more sideways structural bracing and supports.

The box and all online specifications do not provide the width of the track road bed. It is only 85mm between the walkways. For Märklin K-track this means that the track distance for a double line has to be 55mm where the standard track spacings are 57mm and 64.6mm. In addition, the walkways are about 1.5mm higher than the center so using the full 115mm width of the bridge means one has to install some sort of spacer in the middle so that the tracks do not lean into the middle.

There is some interesting information to be found about this bridge and its construction if you Google "Engineering and Contracting Vol 42" from July0-December 1914. Peruse the Bridges article starting on page 63. There are some nice structural drawings as well as detailed information and picture. I can't see the detail very well in Figure 3, but it appears that the initial single curved track across the bridge may have been super elevated.

nice Swiss layout. I suspect the tracks are not 64mm apart, or they widened it on the far side of the bridge.

Here is how wide the Faller kit is.In order to have tracks at 64mm spacing I had to add a flat layer on top so that the two tracks had a flat surface to rest on.

To be fair to Faller Dale, they have made the track spacing on the bridge to NEM spec of 50mm which is correct.Marklin are but one of many manufacturers and Faller don't say the bridge is designed specifically for Marklin; who of course do not follow NEM for track spacing.

I think what should happen is that bridge kit manufacturers should state on the box/description what track spacing they are designed for.

The box and all online specifications do not provide the width of the track road bed. It is only 85mm between the walkways. For Märklin K-track this means that the track distance for a double line has to be 55mm where the standard track spacings are 57mm and 64.6mm. In addition, the walkways are about 1.5mm higher than the center so using the full 115mm width of the bridge means one has to install some sort of spacer in the middle so that the tracks do not lean into the middle.

Hi, Dale, this kit has been on my shelf for a long time. I'm now leaning toward building it into some type of module as my layouts remain "temporary".

Why not just go with the 55mm spacing across the bridge? It's just 2mm less than M standard, and with the straight line passing trains shouldn't have issues. Of course some slight flex-track adjustments would be required on and off the bridge.

Group Question: Anyone mounted catenary? I saw a build once that used Swiss-style continuous "bridge" supports across the tracks to add stability to posts on both sides with bases kitbashed into supports along the bridge.

because 55mm is not a standard track separation for K-track, plus I had already laid the track at the standard 64.x mm spacing (on both side of the bridge) and altering them would make have made it look awful.

If you know ahead of time that the bridge is so narrow, one could plan to have the tracks closer together, so long as you have curves on either side of the bridge where you can hide the transition back to standard spacing

having two together certainly is impressive, but splitting a mainline double track to 4 tracks just to go over a bridge makes no sense to me at all.

It not like one can run 4 trains over there at the same time either. The 3rd and 4th ones will have to stop on the bridge!

Expensive bridges usually would constrict a double track to a single to avoid the expense of additional bridgework, not the other way around. In fact, the prototype for this bridge initially carried a single track for many decades and then a second track was added later.

It is a common theme on many layouts that self made bridges would in reality never be realised due to their over-design or unrealistic engineering attributes. One of the key engineering principles overlooked is often the self weight of the bridge and the cost of building and supporting that weight. There are also those none engineering questions that are so important in all bridge construction, such as; do we need a bridge here? and is it economically viable here?

That said, I love bridges and I love to see the effort and ingenuity people put into their layouts and bridges, they almost always add that extra dimension and after all,these are fantasy layouts with the appropriate degree of artistic license.

because 55mm is not a standard track separation for K-track, plus I had already laid the track at the standard 64.x mm spacing (on both side of the bridge) and altering them would make have made it look awful.

If you know ahead of time that the bridge is so narrow, one could plan to have the tracks closer together, so long as you have curves on either side of the bridge where you can hide the transition back to standard spacing

Coming from/going to the 64.x spacing to 55mm would be more dramatic than 57mm to 55mm. With the narrower spacing I would think it would only take some gentle curving with flex track that could be done over some distance if possible...

because 55mm is not a standard track separation for K-track, plus I had already laid the track at the standard 64.x mm spacing (on both side of the bridge) and altering them would make have made it look awful.

If you know ahead of time that the bridge is so narrow, one could plan to have the tracks closer together, so long as you have curves on either side of the bridge where you can hide the transition back to standard spacing

Coming from/going to the 64.x spacing to 55mm would be more dramatic than 57mm to 55mm. With the narrower spacing I would think it would only take some gentle curving with flex track that could be done over some distance if possible...

I don't know how to respond to this post! I initially thought you had not seen my post but you actually quote it...

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